Building a 300-650 yard gun

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P1huntclub.com

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Let me start by saying that I am VERY new to longer range shooting (never shot past 300 yards for accuracy), but I am getting very fascinated with it. I currently only have a 300 yard range at my house, but my hunting property has a flat area up to 650 yards right at camp (only get down there 6-7 times a year when it is not hunting season)

I am looking to build a 300 - 650 yard gun, but do not know what caliber I want. I currently have a Sako 6mm/284 (yes 6mm and not 6.5mm) with Krieger barrel that has a slow twist so I can only shoot the smaller bullets (65 is what I am shooting now). I also have a 308 with a 20" barrel that will shoot the 168 SMK's great, but they only travel 2800 fps, so I'm not sure that is the caliber I need to start off shooting at 500 yards. They both shoot more or less 1" at 300 yards consistently (with me shooting). Do I try these guns out to 500+ yards, or do I build another one (and we all know I want to build another one or I would not be posting this)?

Any suggestions on calibers? I want a caliber that shoots between 3300 and 3700 fps (I think), but has longer barrel life than the 6.5/284. I want to get 2000+ rounds through it before she needs to be rebarreled. From what I have been reading (on this very site in the benchrest section), the 6.5/284 has a "barrel life" of approx 1200 rounds. Is "YOUR" barrel life, and "MY" barrel life two separate things? For right now, I will be happy to shoot 5" groups at 650 yards. I know I need to take baby steps, and I do not have the time to put into it to be "GOOD", but I want a gun that will get all of the holes in the same general area at 650 yards.

Does this thread belong here, or in another section? Sorry, but being new to this site, I'm not sure where this post goes, but I wanted opinions from people who know, and not people that sort of know (I got one of those living 2 houses down).
 
5-6 hundred

I have an AWC Technologies (click here) .308 with 20" 1.250" Krieger barrel and McMillan A-5 stock. I just got it 3 months ago, and have not really had the time to play with it like I wished. I do think I found the right load for it. I'm loading 45 grains of BL-C2 and a Seirra Match King in 168 grains.

So even with speeds this low, it will still shoot good out to 650 yards and beyond? Being a deer hunter mostly, I'm just not used to my guns dropping 5" between 100 yards zero's and 300 yards targets.
 
Keep it mind that it doesn't matter how fast the bullet is traveling or how much the bullet weighs.
If you hit em you get em..If you miss em you don't.
Find an accurate rifle and then shoot it enough to know the gun.
 
I think the WARP 7 would be perfect!!! This starts as a 300 Win but with a 35 degree shoulder and very minimal body taper. Built a sporter out of it first to see how it would work on a BR rifle. Shoots very small holes and has killed a couple of things this past fall. One of Speedy's creations. I get a SD of less than 12fps but you will have to have dies and a reamer made... I have the print for the cartridge.

The attached sheet has .17 MOA and that is not a mistake --- long story on a custom scope made to use on the rifle.
USOWarp72.jpg
 

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Warp 7 is a 284 Jarrett

From Kenny Jarrett's WWW

284 Jarrett

140 gr. Nosler Bullet...........3450 to 3500 fps
150 gr. Nosler Bullet...........3350 to 3375 fps
160 gr. Nosler Bullet...........3250 to 3300 fps

We are amazed that the 300 Winchester Magnum had never been reduced to 7mm with enough success to be well known. The wheels really began to turn wondering what the exact volume of the case would be. We designed a different case taper than we’ve ever used, our traditional 35 degree shoulder along with a lead angle in the throat to accommodate 140 and 160 grain bullets. We had a reamer made and proceeded to build the .284 Jarrett! After the case fire forming was completed, we did analysis of comparisons to the other big sevens to see where ours fit in.

We checked all of the cased by water volume and this is what we came up with: (Volume to base of neck)

7 mm Remington Magnum ..........73.5 gr.
7 mm Weatherby Magnum ..........78.0 gr.
.284 Jarrett ...............................85.5 gr.
7 STW ......................................98.3 gr.

It’s interesting to note where we were volume wise, 12 grains greater than the Remington Magnum and 13 grains less than the 7 STW.

The next step was to shoot this thing. Foremost in our interest was how accurate it was. If it’s not accurate, the velocity doesn’t matter. The cartridge responded well to a variety of powders and without effort we were under our half minute accuracy with velocities we thought should be correct for this case capacity.

http://www.jarrettrifles.com/petcalibers.aspx
 
6X47 LAPUA...fast twist...a lot cheaper to shoot than the big 30's...mild recoil...quick retury to battery...alot less powder...great for little varmints or paper...don't think I'd be shootin' any big game at those distances...if your going to hunt, use some built on the 30's..nothing like power !!
 
P1huntclub.com said:
Does this thread belong here, or in another section? Sorry, but being new to this site, I'm not sure where this post goes...
Click to expand...

Actually it would probably be better in the Factory/Hybrid Rifle forum and receive lots of replies. (Accuracy related discussions pertaining to factory and modified factory rifles)

Maybe Wilbur will move it if he sees fit. The Centerfire Benchrest Forum is mostly to do with short range Benchrest shooting 100, 200, 300 yards and small cartridges. (Centerfire Benchrest, Competition and Accuracy Related topics)
 
wnroscoe said:
Warp 7 is a 284 Jarrett

From Kenny Jarrett's WWW

284 Jarrett

140 gr. Nosler Bullet...........3450 to 3500 fps
150 gr. Nosler Bullet...........3350 to 3375 fps
160 gr. Nosler Bullet...........3250 to 3300 fps

We are amazed that the 300 Winchester Magnum had never been reduced to 7mm with enough success to be well known. The wheels really began to turn wondering what the exact volume of the case would be. We designed a different case taper than we’ve ever used, our traditional 35 degree shoulder along with a lead angle in the throat to accommodate 140 and 160 grain bullets. We had a reamer made and proceeded to build the .284 Jarrett! After the case fire forming was completed, we did analysis of comparisons to the other big sevens to see where ours fit in.

We checked all of the cased by water volume and this is what we came up with: (Volume to base of neck)

7 mm Remington Magnum ..........73.5 gr.
7 mm Weatherby Magnum ..........78.0 gr.
.284 Jarrett ...............................85.5 gr.
7 STW ......................................98.3 gr.

It’s interesting to note where we were volume wise, 12 grains greater than the Remington Magnum and 13 grains less than the 7 STW.

The next step was to shoot this thing. Foremost in our interest was how accurate it was. If it’s not accurate, the velocity doesn’t matter. The cartridge responded well to a variety of powders and without effort we were under our half minute accuracy with velocities we thought should be correct for this case capacity.

http://www.jarrettrifles.com/petcalibers.aspx
Click to expand...

Not quite but close -- this one was designed for a BR application and in load development there were velocities considerably higher(almost 100fps) but the accuracy was not .4 MOA at 600yds so I compromised but for the competition rifle I will be using much heavier bullets.!!:D
 
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Some conflicting requirements - high velocity with high barrel life. In general, these two characteristics are opposed. What is the ultimate use of this rifle? configuration and weight?

The only way to get high velocity AND high barrel life is to use light for cal bullets ie 22/250 and 55gr bullets.

They work well for varmints and general plinking but are not ideal for LR shooting for score/group. This is because of wind.

I shoot Fclass and you should investigate the many options used there. We have similar needs and most shoot similar distances.

Right now, F(O) is dominated by 6mm, 6.5's. The 7mm's are doing very well at distances beyond 650yds if you can handle the recoil.

Most shoot heavy for cal/high BC bullets from 2800 to 3000fps. These bullets don't like going faster in general - don't need to either.

If you spend alot more time at 300 then 650yds, the 6BR is really hard to beat. The improved versions allow you go faster. The longer 6XC/47L's go faster still.

Lower recoil, cost, wear and tear. Wonderfully accurate and good in the wind.

I compete with a 6.5 Mystic which is my version of the 260AI. 2900fps for a 139gr Scenar is easy and this bullet is superb at all distances. Better wind bucking then the 6mm but higher recoil.

All of these will easily meet your 2000 rd requirement.

If you plan is to throw in some hunting, then the 6.5 is a min but the 7mm/30's become better choices. However, you trade recoil/wear and tear for downrange horsepower.

I am presently playing with a fast twist 223 and 75/80gr Amax. What a hoot. Low recoil, dirt cheap, lasts forever and very accurate all the way out to 1000m. Not as good in the wind as the above but in the same ballparks as 308's.

Jerry
 
mysticplayer said:
Some conflicting requirements - high velocity with high barrel life. In general, these two characteristics are opposed. What is the ultimate use of this rifle? configuration and weight?

The only way to get high velocity AND high barrel life is to use light for cal bullets ie 22/250 and 55gr bullets.

They work well for varmints and general plinking but are not ideal for LR shooting for score/group. This is because of wind.

I shoot Fclass and you should investigate the many options used there. We have similar needs and most shoot similar distances.

Right now, F(O) is dominated by 6mm, 6.5's. The 7mm's are doing very well at distances beyond 650yds if you can handle the recoil.

Most shoot heavy for cal/high BC bullets from 2800 to 3000fps. These bullets don't like going faster in general - don't need to either.

If you spend alot more time at 300 then 650yds, the 6BR is really hard to beat. The improved versions allow you go faster. The longer 6XC/47L's go faster still.

Lower recoil, cost, wear and tear. Wonderfully accurate and good in the wind.

I compete with a 6.5 Mystic which is my version of the 260AI. 2900fps for a 139gr Scenar is easy and this bullet is superb at all distances. Better wind bucking then the 6mm but higher recoil.

All of these will easily meet your 2000 rd requirement.

If you plan is to throw in some hunting, then the 6.5 is a min but the 7mm/30's become better choices. However, you trade recoil/wear and tear for downrange horsepower.

I am presently playing with a fast twist 223 and 75/80gr Amax. What a hoot. Low recoil, dirt cheap, lasts forever and very accurate all the way out to 1000m. Not as good in the wind as the above but in the same ballparks as 308's.

Jerry
Click to expand...

I agree with everything that you say except that a 22-250 has a high barrel life. I've shot out a lot of those.
 
6BR or 6BR IMP, 8 tw shooting vld bullets. They hold all the IBS 600 yds records. How does 0.749" sound with a 6BRX at 600 yds. The NBRSA record is 0.58XX" with a 6 Dasher.

Mark Schronce
 
necking down the 300 win mag started in 1963 when the round came out. i've had 2 rifles based on the 300 wm first on was a 7mmx300 wm called 300 Apollo. the second one was a 6.5mmx300 wm called it the 6.5 win nag, barrel lasted exactly 800 rnds. the 7mm gun is now a 358 norma mag and i still hunt with it every now and again.
 
my reason for building

Mystic... thanks for your info... My main reason for this gun is paper shooting only. I am a typical TEXAS hunter trying new things without the "kill" factor (which is not so typical). It's a way I can get out, and shoot smaller groups at longer distanes than my other hunting buddies. I have no intention of entering any competitions, and have no intentions of doing any "structured" shoots. So the gun does not have to shoot .38xx at 600 yards. In fact, if I can just shoot 3" groups at 600 yards, I will be tickled camo. I just have fun shooting custom made rifles. I have plenty of 100-300 yard guns for hunting, and living in Texas... I limit my shooting to pretty much 300 yards from all my hunting areas.

With my requirements, am I over thinking this whole thing? Should I just pick a 6mm br (running at 3000 fps) and have fun shooting it at home at 300 yards, and then have even more fun shooting it at 650 at the ranch?
 
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